I'm working on a site that uses images diagonally aligned. The images are fairly simple and have some text inside so I can achieve the effect using either images or the CSS3 transform: rotate and border-radius properties, granted, with all the proprietary extensions.
However I'm wondering if there are significant advantages for using one over the other. I'm thinking maybe the CSS-only alternative would load faster, but a downside would be the use of more code for each image. Although using images I'd still have to do a lot of positioning for each element. Also, the CSS in the first case would not validate using browser-specific extensions, how important is this if I still make sure the site is correctly displayed in most browsers?
Is there a general approach for using either one of these options? What would you recommend?
The use of CSS3, versus images, is best answered by your need to support Internet Explorer (or other older, or CSS3-unaware, browsers): if a large portion of your user-base browses with IE then you should use images.
If you're only interested in the later, more standards-compliant, browsers (possibly including IE9, but I've no experience with it as yet) then CSS 3 is likely the better option, since it might involve a larger CSS file, but it does allow you to switch your layout more easily in future, without having to create/recreate a new set of images for the new design.
You could, of course, combine both approaches: use CSS 3 for the compliant browsers, but include an IE-specific stylesheet, with conditional comments, to supply the images as, perhaps, background-images to build up the design. This is, of course, likely to be a lot of work, though.
I would honestly recommend an image for this. CSS3 is cool, but browsers that don't support it might break your layout. Also (possibly more importantly), text really needs proper anti-aliasing to be readable when rotated or scaled, and you can get finer control over that with an image.
Two things I think you should consider here:
Images are a killer for those on mobile devices. So if you are targeting those with mobile or expect a large mobile audience, you may want to reconsider using a lot of images (and having your users pay a ton in bandwidth).
The text in your images (if you use images) will not be searchable by search engines and will not be accessible for those with accessibility issues, unless you are good at filling in your alt tags. ;-)
Related
I'm trying to create a game that uses buttons (and text areas) that are semi-transparent (Alpha of about 60%). I can do almost everything I want in XHTML and CSS, except for these semi-transparent items. So I'm looking for the easiest way of creating semi-transparent images on my web pages.
Ideas so far:
Create PNGs with semi-transparent pixels. This is supposed to be possible, and there are well-defined interfaces for defining an Alpha channel using PHP and the GD package. Problem: I tried this, but the images were opaque in all the browsers I tried (Chrome, IE8, FF).
Do it in Flash. I know how to use Flash(*) from some work I did before I retired. Problem: Flash is priced for the professional developer, not the hobbyist.
(*) Well, Flash 8. But as I understand it, even with newer versions I can continue to create movie clips the old way, they just get translated into a bunch of AS. And it's supposedly possible to continue using AS2, although you can't mix AS2 and AS3.
Do it in Flex. Problem: interfaces best described as arcane. Even using suggestions from experienced Flex developers, trying to include code from another mxml file (other than as a class) was a PITA.
Use SVG. This looked promising. The SVG syntax is basically XML, the element tags are reasonably obvious, and the interaction of attributes only slightly arcane, and there are plenty of examples in the tutorial. But... about half of current browsers will not support using SVG in an <img> tag. You have to use <embed> That means you can't put it inside an <a> or <button>. Even using embed, I got what look like "broken image" icons in IE8.
As I'm writing this, I notice several items under "similar questions" that look promising. But when I look at them, they use attributes that are not mentioned in the CSS spec: opacity, filter:alpha, and rgba. When working in a complex language, I really prefer to have the complete language spec open in another window, or to have the equivalent dead-trees version (e.g., the O'Reilly salmon book Cascading Style Sheets, The Definitive Guide, which sits on a bookshelf next to my desk.
So I'm asking for recommendations. If the consensus is to use SVG, I'll post my code and see if people can tell me what I'm doing wrong.
The CSS "opacity" property is perfectly valid. It is part of CSS3, and is supported in all browsers (*).
http://caniuse.com/css-opacity
Or you can use semi-transparent PNGs, as Alvaro demonstrated. They should work just fine. Not sure what happened with your attempts, but you must have done something wrong.
Note for versions of IE <= 8, you need to use the "filter" property instead.
https://developer.mozilla.org/en-US/docs/Web/CSS/opacity
I don't know what problem you have with PNG's. Imo the best and easiest option by far. And they look as they should in all browsers from my own experience.
check this out: http://jsfiddle.net/BDLYG/
(and here a code I need to add)
If you have most users with the 'modern' browsers, I would say go with SVG. If you do, post here, and I'll be glad to help.
Many thanks for all the useful answers. I'm currently using a combination of CSS and PNGs (generated via PHP). I could have gotten along with just CSS, but I decided I wanted to change the opacity of the background when the user hovers over the button -- but keep the text opaque. It's easy to change the opacity of the whole thing, but (as far as I can tell) not of just the background.
I also experimented with SVG, and it also works fine, but it requires extra computation so I chose the simpler (for me) approach of CSS and PHP. I'm already comfortable with those two languages, just needed to be introduced to the newer stuff in CSS3 and the one extra function call needed to make alpha work in PNGs generated by the PHP GD package.
Use of gradient images is very common among developers for styling a page. Gradient images are used in many places from styling the navigation bar to styling the background. Technique like repeating a small image in either direction is also common.
One more way to style and give this effect is by using multiple div's one below another with different color, the latter being a little lighter than the former. In the most simple scenario doing so would include only a small script. So, no problem of writing a lot of markup, just some simple code.
The only concern that remains is speed and performance.
Speed
The script, more precisely the function would be much shorter in size than a image. So, in matters of speed the latter method seems more good.
Performance
Today's browsers are very powerful, so the difference between displaying an image and executing a function is negligible.
Css management
Obviously, problems like positioning would be another concern but we do struggle with such problems in every day life. The problem is no greater than overlapping two div's and setting their z-index. The whole gradient div's can lie inside one parent div.
So having addressed the issues of performance and speed isn't using Gradient div's a much better approach than using images?
It's an alternate approach, yes. But not a good one. You get zero points for:
Maintainability
Scalability
SEO
Separation of presentation from content
Furthermore, to say that we needn't worry about performance since today's browsers are more powerful is a gross assumption.
Actually, I think the second option you describe (creating multiple divs with atering colour) is downright terrible.
You're altering markup for the sake of styling. That's a no-go.
It's a common thing among users to disable JavaScript. What happens then?
As you said yourself, positioning mayhem.
When it comes to performance, I would be more cautious than to state it's no longer an issue. Especially with the dawn of mobile browsers in mind.
Such styling would be harder to understand and maintain. Particularly when your team changes someday.
Also, there are two other ways to implement gradients.
CSS gradients - limited to simple variants and requiring a lot of CSS to provide decent cross-browser capabilities. You can try this generator get a taste of these: http://www.colorzilla.com/gradient-editor/
SVG backgrounds. These allow you to create just any gradient you wish. You can use an svg file in your CSS just like any other image. However, some browsers don't support this feature. Here's a table showing when it's an option
Using images is the most reliable option, while combining SVG with normal images (for these browsers that don't support SVG) seems the most flexible approach.
I'm trying to create a trapeze like shape using any number of techinques so that it will be as much as possible. the shape i'm trying to create a shape like this:
(there will be content inside the shape [imgs & txt])
so far, the possible ways of doing that are: masking (webkit) and SVG effects on html content (firefox). but I cant seem to find any way to make this work with IE and opera.
So if anyone could show me how to do this, it will be greatly appreciated.
There are a few options for creating non-rectangular shapes using CSS, but they are all hacks. This isn't something that you'd normally expect to do using CSS.
The most well known technique is triangles made using borders. It is very much a hack, and would require using multiple elements for a single shape. I wouldn't suggest using it on a production site.
The other CSS solution I can think of would be to use an extreme border-radius setting to modify the shape of the box. This is less hacky, but won't work in IE8 and lower, so fails your criteria.
You say you've tried the SVG approach and given up on it because it doesn't work in IE8. It's worth pointing out that while IE doesn't support SVG, it does support VML, which is a competing vector graphics format. SVG is now standardised, so VML will fade away, but older IEs will continue to support it.
Therefore the solution I'd go with would be to use SVG by default, and VML instead on IE7/8. The good news is that there are several Javascript solutions which make this easy.
One is Raphael, which allows you to draw SVG/VML images using Javascript. Commonly used for real-time graphs, etc.
There are also a number of solutions which simply convert SVG to VML. For example http://code.google.com/p/svg2vml/. But there are several others available.
Hope that helps.
As you suggest, masking and SVG are the way to go. These will be supported in future browsers. If you must be backwards compatible with IE, look into the IE "filter" for CSS (google "ie filter").
Be forewarned: It's very unintuitive (compared to CSS3) and generally a bitch to work with. If your goal is to make the page look identical to the CSS3 version, it will be difficult and you're probably better off using images.
I've been reading a lot of ways recently of how to avoid having to use Photoshop for things like gradients and shadows on buttons, when you can use CSS3 Box Shadow for such features. Now this is great, but obviously legacy browsers and most IE browsers don't yet implement CSS3 features, so my question is, why save yourself extra work in Photoshop when you can use CSS3 but then HAVE to use Photoshop for other browsers to see the desired effects? Isn't that just extra work?
you can use CSS3 but then HAVE to use Photoshop for other browsers to see the desired effects?
Often you don't really care whether the other browsers see the desired effects. If it's just a subtle background gradient effect, the site's going to work fine and still look reasonable with a flat background in downlevel browsers.
Compatibility was more of a problem when CSS 2 Positioning was at this stage: an unsupported positioning feature could lead to an unusable layout. But for essentially frivolous effects like backgrounds, borders and shadows, it's not critical if the effect goes missing.
There are a few reasons. From a developer/designers perspective, using CSS3 can be more flexible. An image is more or less just a static image. With CSS you can use script or CSS to animate or adjust the styling, and have advanced integration between the various technologies. This allows you to be able to do some things that are not possible or difficult just using images.
The page weight is also lower usually when using CSS, which allows the page to load faster, especially on slow connections or mobile devices. It also reduces HTTP requests (although you can use data uris too) which reduces latency and thus speeds up page loading.
Using CSS is often more maintainable and quicker, as you can adjust say a background colour or a shadow quickly just by changing the CSS, while with images you have to open up photoshop, edit the file, resave, etc. This is fantastic for quick tweaks.
There are also some people (myself included) that are much more comfortable in code than they are using graphics packages. For me it is easier to use CSS, but your milage may vary.
Also from the browser perspective we want to move the web platform forward and increase the capabilities. SVG is an example of another technology that doesn't work across all browser versions yet, but adds a lot of power. Although it may not be possible to deploy sites using certain CSS3 properties or SVG without fallbacks right now (depending on your audience or client) there will be a time in the future when old browsers are dead and what we are adding today works for all users. There was a time when most of CSS2.1 wasn't supported for example, while now you can rely on most of it if you don't need to design for IE6.
There are some parts of CSS3 that you can happily use without fallbacks, if you have a client that doesn't require all browsers to look the same. border-radius is an example, or giving a solid colour fallback to old browsers and applying transparency for newer browsers.
The world is moving forward, you can't ignore it. as long as old browser will show a button and new browser will show a more nice one, you are ok.
Otherwise, we were still be working on VT100... as why using "Windows" if most monitors doesn't support more than 4 color graphics and has 80X22 resolution....
If your bosses accepts the idea of having two versions of looks and feel and a warning. CSS3 is a good idea.
So, you use CSS3 features in your code and forget about the browsers that are not compatible -- they will see the "low-graphics version", you might want to issue a non-intrusive warning (like the one we get as alerts in StackOverflow), saying, "Your browser is not compatible with CSS3. To see this website in high graphics please upgrade your browser. Click the link here to update now."
But, depends on where you work. Big companies with lot of resources may like to stick with Photoshop and smaller once may like a light-weight CSS3 code that degrades silently in non-compatible browser.
Well you can always use ChromeFrame, to impose nice behavior on IE. Assuming that a lot of products will insist for it the near future (yeah we can argue against this), chances are that most IE users will have chromeFrame even before your application would insist for it. Once you take a decision on this, decision on using CSS3 properties or HTML5 elements is - well - hell yeah!!
Marvin
Having asked this question How to reach CSS zen?, I now understand that the issues I have are mostly related to positioning. I've found some articles telling that CSS is not always good enough as a layout system.
http://echochamber.me/viewtopic.php?f=11&t=40154
http://www.flownet.com/ron/css-rant.html
http://blog.workaround.org/2009/03/17/dont-abuse-css-for-page-layout/
Do you as CSS designers limit yourselves upfront to designs that CSS can handle? Should I avoid things that seems perfectly easy are in fact difficult to do with CSS?
Of course you limit yourself. As a designer, you should always think about the medium you're working with. If I were designing a magazine ad, I wouldn't be thinking about animations or video. There are certain rules you must adhere to, and it doesn't make sense to ignore that.
But of course, rules were always meant to be broken.
Why?
If you are "designing", why would you limit yourself based on a the limitation of one technology? When you design your site, you should always try to achieve the most usuable interface for the user.
If you do limit yourself, then you are just asking for the site to not be used, and then what's the point of creating it?
I don't limit myself upfront to any designs that CSS can handle (within reason of course), just figure out your design and there will be someway that you can get it looking right using CSS, but it might involve a lot of hair pulling, especially if IE6 is involved!
When implementing a web design (assuming I've got an image/drawing of what the site will look like) I always follow these steps:
I look at the design and determine what components it has. Examples are navigation areas, headers, content areas, and so on.
I implement (X)HTML that can represent the content areas without really taking the design into account (there are certain things such as content order that I use the design to determine.)
I start making the CSS and images needed for the site to look the same way it did in the original design document. Depending on the complexity of the design, I might come up short of elements to use for styling the page, and may end up adding elements that don't really make sense for the content. I try to avoid it as much as possible, though, and I try to create the elements in a way that isn't obtrusive to the content.
As you can see, I never limit the design to the capabilities of CSS. CSS comes last. Now, depending on the complexity of the design, it might not look exactly like it did in the original design document, but the goal is always to make it as identical as possible, while still maintaining clean HTML so that the design can easily be updated in the future.
Most layouts I find can be done with CSS. There are a very few exceptions (normally to do with verically centering text).
For me the main factor which limits my designs is a reluctance to use huge background images. If an effect can't be done by combining/repeating a few tiny bg images I tend to reject or tweak it. Eg a diagonal gradient on a box with curved corners which could be any height might fall into this category using CSS2.1
Almost every painter limits themselves to paint on canvas, almost every sculptor makes 3D shapes from stone or clay or metal...
But there's also the few who dream new dreams and create new things. Some flop, some shine.
Should you limit yourself based on what CSS can do with layouts? Not completely. I say dream big.
Once you've got your dream design, either figure out how to create it, find a technology other than CSS that can do it, or go start inventing!
You can do absolutely almost anything using CSS 2.1 as far as layout. Its a complete pain in the ass that has no reason to ever exist, but you can do rounded corners (using background images), gradient backgrounds (more background images) and all kinds of other bloated crap you don't need all together and still not completely destroy the semantics of your HTML.
Doing all that garbage and still attempting to be standards compliant reduces usability, because its the designers who need round corners and other frivolous crap and not the users. Usability tests have confirmed this. Sites that are bloated to accommodate presentation and usability at the cost of semantics and efficient fail in usability tests compared to their competition. I work for a website that gets several million visitors a day and I have seen the results of our usability tests.
CSS provides a very good way to create an overall design that easily can be changed by small changes in one CSS file, and instantly applies the design changes to all your pages. Of course there are things that are tricky to do with CSS, and in those cases you might want to do it in other ways, but even if your layout is mainly based on CSS, doesn't mean that you can't do some special parts using other technology! You can mix!
So you don't limit yourself when you go for CSS. You just make use of a powerful technology that can be used in perfect harmony along with others!